AD7985BCPZ

Overview

The AD7985BCPZ is a 16-bit, 2.5 MSPS PulSAR analog-to-digital converter (ADC) manufactured by Analog Devices Inc. It utilizes a successive approximation register (SAR) architecture and features a pseudo-differential analog input voltage range from 0 V to VREF, with VREF supporting up to 5.0 V. The device operates on a single 2.5 V analog/digital supply and a separate 1.8 V to 2.7 V digital I/O supply. Key performance metrics include an integral nonlinearity (INL) of ±0.7 LSB typical and ±1.5 LSB maximum, and a signal-to-noise ratio (SNR) of 88.5 dB with the internal reference or 90 dB with an external reference. Power consumption is 15.5 mW at 2.5 MSPS with an external reference and 28 mW with the internal reference.

Feature Summary

• Features a low-power 16-bit SAR ADC architecture with no missing codes and zero pipeline delay for immediate data availability.
• Includes a high-precision 4.096 V internal bandgap reference with ±10 ppm/°C drift, which can be powered down to allow external reference inputs up to 5.0 V.
• Supports versatile serial interfaces compatible with SPI, QSPI, MICROWIRE, and DSP standards, including daisy-chaining capabilities via the SDI pin.

Applications

• Battery-powered equipment requiring low power dissipation
• Automated test equipment (ATE)
• Data acquisition systems
• Medical instruments

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current documentation to ensure correct package type and temperature range. Confirm that the component matches the required RoHS compliance status and lead finish specifications for your assembly process. Cross-reference the datasheet revision to ensure all electrical parameters align with your design requirements before finalizing procurement.

Selection Notes

Select this component when a 16-bit resolution and throughput up to 2.5 MSPS are required in a compact LFCSP package. Consider the internal reference for simplified designs or an external reference if higher SNR or different voltage ranges are needed. Ensure the host system supports the required 1.8 V to 2.7 V logic levels for the digital interface.

Part Context

The AD7985 belongs to the Analog Devices PulSAR family of low-power, high-speed SAR ADCs. It is pin-for-pin compatible with the 18-bit AD7986, allowing for potential resolution upgrades without PCB layout changes. The device is designed to operate within a specified temperature range of -40°C to +85°C.

Replacement Considerations

The AD7986 is a pin-for-pin compatible alternative offering 18-bit resolution. For lower speed requirements, the AD7980 or AD7983 may serve as alternatives within the same family.